The present invention relates to a system and a method for tracking, storing, and maintaining objects or personnel having RFID tags attached thereto in a defined zone or geographic area such as buildings, factories, tractor-trailers, aircraft, railroad cars or other areas where the zones have plurality of points of access or within a defined area. The present invention further relates to an improved object or personnel tracking and control system which makes use of a portal RF antenna with infrared optical sensors that can scan the object or personnel RFID tag and detect and determine the direction in which objects or personnel are moving. With the use of IR heat sensing and motion sensing sensors, the presence or absence of an object without an RFID tag and the moving direction of such object as well as whether said moving object is a person or not can be determined.
A number of different methods has been used in the past to track the location of large numbers of objects (pallets of cargo, packages etc.) or personnel located within buildings, trailers, containers, buses, and aircrafts. These methods have been used for purposes of tracking cargo, employee attendance, school attendance, or logging in passenger manifest along with carry-on luggage. The oldest of this method is by keeping an inventory register of each warehouse or vehicle content and it's delivery records in a paper journal, attendance punch cards, or more recently, with the use of computers or a hand held computerized device and database. The accuracy of inventory or personnel registry depends on each individual operator to properly input information relating to packages or personnel. Such a system is limited to assessing the number of objects or pallets and cannot accurately identify the location of each and every pallet, package or personnel and entails significant costs from a human resources standpoint.
As one might expect, a variety of different approaches has been taken to solve the problem of monitoring large numbers of vehicles, cargo pallets, packages and/or personnel at a specific location (such as a warehouse or office building) or in a vehicle/trailer. From a security perspective, certain applications for purposes of monitoring cargo pallets, packages, luggage, personnel and/or passengers relating to vehicle content, warehouse site, retail stores, schools, at ports of entry, and airports also require tremendous recourses including security guards, video monitors, magnetic tag detectors, metal detectors, access controls, bar-code readers as well as mechanical or optical counters. While such approaches may reduce the incident of theft, hijacking, personnel attendance, they are not useful in addressing the primary problem contemplated by the present invention, namely, how to keep track of the location of a plurality of cargo pallets, packages and/or personnel carried in various modes of transportation and/or within a defined geographic area or zone such as warehouses or buildings.
One such system is illustrated in U.S. Pat. No. 4,009,389 to Lindholm. Apparatus for the automatic counting of passengers that detects the number of passengers entering and/or leaving a collective passenger vehicle projecting a pair of light-beams of invisible light across passenger door way and detecting with the light beam in response to first and second light is disclosed.
Another example is an automatic counting system for passengers disclosed in U.S. Pat. No. 4,528,679 issued to Shahbaz et al. The automatic counting system counts the passengers moving into and out of a common carrier vehicle. Three ultrasonic detectors are used to determine the presence and absence of passengers, while the sequence of detection of passengers at the three different ranges establish a count of number of passengers entering or leaving.
U.S. Pat. No. 5,485,347 issued to Miura discloses a situation Guiding Management System used with plural of cars constituting a train, and an up/down counter for counting passengers getting on and off each car with passenger sensor/counter provided at doorways and pass ways of cars. The infrared temperature sensors element are used for sensing temperature and a pair of photo sensors serves as direction sensor for determining whether a passing passenger is getting on or off a car.
U.S. Pat. No. 5,068,537 issued to Ishikawa et al. describes a passenger number sensor System wherein a plurality of infrared ray sensors are disposed on a straight line to detect temperature change, a plurality of optical lenses are provided the corresponding one of the plurality of infrared sensors, and a counter is provided to select one of the addition value in a predetermined range according to sense pattern on the temperature change of infrared ray sensors and to add the selected addition value to accumulate count value.
U.S. Pat. No. 5,866,887 issued to Hashimoto et al describes an apparatus for detecting the number of passers. A plurality of rows of distance variation measuring sensors is provided on a ceiling. Each of the distance variation measuring sensors includes a light emitter and a light receiver in an orthogonal direction to the direction along which human pass. The number of passers is detected on the basis of the number of the distance variation measuring. The traveling direction of human bodies is detected on the basis of the change in distance.
U.S. Pat. No. 6,255,946 issued to Kim discloses a system for detecting the presence and direction of an object passing through a gate. The system uses a first and a second infrared beams to emit reflector, receives a mixed beam superimposed by the first and second beams reflected by the reflector, and determines the presence and direction of the object passing through the gate on the mixed beam
U.S. Pat. No. 5,661,457 issued to Ghaffari et al. teaches a directional antenna configuration for a tracking system used in an article tracking. The antenna configuration includes a pair of shorted loops antenna one on respective side of portal. The antenna configuration also includes a second pair of passage antennas arranged in parallel to the path of travel through the doorway. The antenna configuration permits detection of direction of movement of marked object through a portal.
U.S. Pat. No. 5,708,423 issued to Ghaffari et al. discloses a zone-based tracking and Control System incorporated with a data processing system that maintains records of a plurality of objects. Each object has a marker. At least four sensor devices are installed on each side of the respective doorway. Each marked object is expected to move through the doorway. The sensor devices detect from the identification signal a direction in which object is being moved. The data processing system receives the detection signal and maintains a data record indicating object present location in the building.
U.S. Pat. No. 4,009,389 issued to Lindhom, U.S. Pat. No. 5,485,347 issued to Miura, U.S. Pat. No. 5,068,537 issued to Ishikawa et al, U.S. Pat. No. 5,866,887 issued to Hashimoto et al, and U.S. Pat. No. 6,255,946 issued to Kim discloses using optical sensors for detection of directional movement, and counting of human at an entry/exit point.
The teachings in the prior art are not capable of authenticating objects, passers or passengers passing through a particular entry/exit point. U.S. Pat. No. 4,528,679 issued to Shahbaz discloses a similar art using ultrasonic sensors instead of optical sensor. U.S. Pat. No. 5,661,457 and U.S. Pat. No. 5,708,423 issued to Ghaffari disclose asset tracking by use of multiple portal antennas for reading RFID markers and indicating directional movement of objects or personnel carrying markers. The art found in Ghaffari is useful but not practical in use. In order to fill an average trailer or building entry/exit way with RF field, an antenna loop is being used to cover an entry/exit opening area usually about 8 feet (4 m). Since RFID read antennas radiates a 360 degree RF field, as per Ghaffari teaching, in order to detect marked objects or personnel directional movements, minimum of 2 antennas use is required on one side towards an entry way (one after the other, along the entry way), these 2 antennas have to be away from each other by at least 8 feet to allow the RFID antenna reader CPU to detect directional movement of the object or person carrying marker.
First the reader must determine the actual physical location of a moving object or personnel carrying a marker by determining which one of 2 antennas interrogated first and which one interrogated second in order to register a marked object or personnel direction movement detection, depending on physical position of the object or personnel carrying RFID tag at the time of antenna reading. If antennas are less than 8 feet apart, the reader CPU cannot differentiate the tag position because both antennas can read a particular RFID tag at the same time even though Ghaffari discloses only one antenna reading being initiated by the reader CPU at a given time to avoid RF collision. Ghaffari requires a large unusable area in an entry/exit way. One cannot store objects or seat tagged passengers in an entry/exit way (Half of a container, trailer, passenger car) where such antennas are installed. In order to avoid false marker reading, one has to consider unusable valuable space to be wasted for antennas use. Unusable space is a crucial matter, especially in a cargo trailer, passenger car or within small building with partitions.
It should be noted Ghaffari teaches use of 4 antennas in a portal entry/exit for moving marker directional detection. The antennas are operating one at a time interval, one after the other in order to avoid RF collision, thus delaying marker reading speed. Therefore, an object or personnel carrying the marker passing portal antenna zone at fast speed will not be detected, or even if it is detected, the CPU will not be able to differentiate object or personnel carrying marker movement direction. Finally, since Ghaffari relies only on an RFID antenna interrogation system to detect movement of marked object, one can pass a marked object behind a antenna panel, a wall patrician, or an object or personnel tag on the outer side of a cargo trailer, or a passenger car without physically going through the portal and falsely log an object or a personnel into the system database.
Although the prior art cited above is useful, none of the inventions include a secure portal scanner for tracking objects and personnel, a portal scanner that can ascertain in a particular location the presence of a particular objects or particular personnel being carried by several modes of transportation such as vehicles, tractor-trailers, or within a defined geographic area such as warehouses and buildings. It is accordingly a substantial need to provide a secure electronic vehicle, cargo, and personnel tracking information system, which uses a portal scanner for tracking the present location of in a plurality of modes of transportation or at a plurality of physical locations.